The present invention generally relates to fluid droplet ejection systems and, more particularly, to a new and simple ink droplet ejection system for an ink jet printer or the like which can eject droplets of ink without using a vibrator.
Various propositions have hitherto been presented in connection with ink jet printers. Archetypes of most of known ink jet recorders are a so-called Stemme type ink jet printer represented by U.S. Pat. No. 3,747,120 and a Silonics type ink jet printer represented by U.S. Pat. No. 3,946,398. These two types of ink jet recorders commonly include a vibrator which is operably mounted on an ink ejection head. Vibration of this vibrator causes the velocity or pressure of an ink inside the ejection head to vary so that a droplet is separated from a continuous stream of ink being ejected from the ejection head.
Such an ink droplet ejection system, however, cannot be freed from uneven energy distributions to the liquid due to the use of a vibrator, unless the force acting on the vibrator are duely adjusted and controlled. Unevenness is also encountered in the electromechanical convertion efficiencies of vibrators themselves. The result is inconstant intervals between adjacent ones of successive ink droplets. Meanwhile, the construction is so intricate that a force initially acting on the vibrator must be adjusted and care must be taken to avoid interactions between the vibrator and a vibrator retaining member or those between the liquid and the vibrator retaining member.